01 /Why lunar dates feel confusing
The Gregorian calendar is solar. The Chinese calendar is lunisolar, so its months follow lunar cycles while the year is adjusted to stay aligned with the seasons. That adjustment is why some years include a leap lunar month.
A leap lunar month is not the same thing as February 29. It is an extra lunar month inserted in certain years. If a family record or festival note says a date is in a leap month, the converter needs that detail to return the right Gregorian date.
02 /Zodiac years do not start on January 1
For many users, the biggest surprise is the zodiac animal. Someone born in January or early February may belong to the previous Chinese zodiac year because the zodiac year changes at Chinese New Year.
That is why a date-of-birth lookup should use the exact Gregorian date, not only the birth year. The Chinese zodiac calculator by date of birth handles that boundary directly.
